EXCEPTIONALLY HIGH YOUNGS MODULUS OBSERVED FOR INDIVIDUAL CARBON NANOTUBES

CARBON nanotubes are predicted to have interesting mechanical properti es-in particular, high stiffness and axial strength-as a result of the ir seamless cylindrical graphitic structure(1-5). Their mechanical pro perties have so far eluded direct measurement, however, because of the van; small dimensions of nanotubes. Here we estimate the Young's modu lus of isolated nanotubes by measuring, in the transmission electron m icroscope, the amplitude of their intrinsic thermal vibrations, We fin d that carbon nanotubes have exceptionally high Young's moduli, in the terapascal (TPa) range. Their high stiffness, coupled with their low density, implies that nanotubes might be useful as nanoscale fibres in strong, lightweight composite materials.